Flexible polyurethane foams are generally prepared by reacting an organic polyisocyanate and a polyol in the presence of a blowing agent, a catalyst and optional auxiliary additives. The blowing agents used in this application were halogenated hydrocarbons, such as freon. In recent years due to environmental considerations, there has been a trend away from the use of halogenated hydrocarbons.
Among the large number of patents which deal with flexible polyurethane foams note might be made of U.S. Pat. No. 3,067,148 which disclosed a process for the preparation of cellular polyurethane entailing reacting water, an organic isocyanate and a mixture of trihydric polyalkylene ether with a specific tetrahydric organic compound. Also relevant is U.S. Pat. No. 4,569,952 which disclosed a certain addition product of an alkylerne oxide and an aromatic amine which additive is said to contribute to the load bearing properties of soft, flexible polyurethane foams. An amine containing reactive mixture useful in the preparation of flexible polyurethane foam has been disclosed in U.S. Pat. No. 4,876,292. Also relevant in this connection are U.S. Pat. Nos. 4,950,694 and 4,970,243 as well as European Patent Applications 358,282 and 429,103 all of which disclosed processes for the preparation of water-blown polyurethane foam.
Also presently relevant is U.S. Pat. No. 4,048,221 which disclosed dihydroxy sulphonate containing ether groups and a process for their preparation. The sulphonates are said to be suitable as monomers for the preparation of acid-modified polyurethanes. Also relevant is U.S. Pat. No. 4,056,564 which disclosed dihydroxy sulphonates containing ether groups.